<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>3.全选和反选</title>
  </head>

  <body>
    <div id="app">
      <div>
        <span>全选:</span>
        <input type="checkbox" v-model="checkedAll" />
        <!-- computed是属性 -->
        <button @click="checkedAll = !checkedAll">反选</button>
        <ul>
          <li v-for="(item,index) in arr" :key="item.name">
            <input type="checkbox" v-model="item.checked" />
            <span>{{item.name}}</span>
          </li>
        </ul>
      </div>
    </div>
    <script src="../vue.js"></script>
    <script>
      const app = new Vue({
        el: "#app",
        data: {
          arr: [
            {
              name: "猪八戒",
              checked: false,
            },
            {
              name: "孙悟空",
              checked: false,
            },
            {
              name: "唐僧",
              checked: false,
            },
            {
              name: "白龙马",
              checked: false,
            },
          ],
        },
        computed: {
          checkedAll: {
            get() {
              return this.arr.every((item) => item.checked);
            },
            set(value) {
              this.arr.forEach((item) => (item.checked = value));
            },
          },
        },
      });
    </script>
  </body>
</html>
